feat(packages): add commit script to automate commit message generation

packages/commit/default.nix

@@ -0,0 +1,24 @@
+{ pkgs, ... }:
+pkgs.writeShellScriptBin "commit" # bash
+  ''
+    PROMPT="Please generate a one-line commit message using."
+    GUIDELINES="1. Use conventional commit syntax, following the context."
+    NUM_ANCESTORS=0
+    while [[ $# -gt 0 ]]; do
+      case "$1" in
+        --num-ancestors | -n)
+          NUM_ANCESTORS="$2"
+          shift 2
+          ;;
+        *)
+          echo "Unrecognised argument: $1. Exiting..."
+          exit 1
+          ;;
+      esac
+    done
+    CONTEXT=$(git --no-pager log -n 10)
+    DIFF=$(git --no-pager diff HEAD~$NUM_ANCESTORS)
+    RESPONSE=$(aichat "$PROMPT\nGuidelines: $GUIDELINES\nContext from git log: $CONTEXT\nDiff from git diff HEAD: $DIFF")
+    #TODO: revise commit message
+    git commit -am "$RESPONSE"
+  ''